1. Field of the Invention
This invention relates to a hand-held automatic firearm, particularly to a trigger mechanism for such firearm, which mechanism comprises a catch lever, which is pivoted on a transverse axis and is provided at its forward end with a pivoted catch pawl, which in a catching position engages a catching lug of a slider to arrest the slider as it moves forwardly from a rear position, to which the slider, which constitutes a part of a firing mechanism of the firearm, has moved against spring force when a round has been discharged.
2. Description of the Prior Art
In firearms provided with such trigger mechanism the slider, which may consist of a breechblock or of a carriage which by means of a cam mechanism cooperates with a transversely displaceable firing chamber or another part of the firing mechanism is restrained from performing a forward movement which would be required for the discharge of a round and is released only from time to time for the discharge of a round. To restrain the slider, the catch pawl is pivotally moved into the path of the slider to catch the slider as it tends to advance under its spring bias. As is apparent from U.S. Pat. No. 4,745,843 the catch pawl, which is pivoted to the catch lever, is supported relative to the catch lever and relative to a trigger housing and the catch pawl itself constitutes a member which controls the movement of the catch lever to its catching position and to its releasing position. That arrangement involves a considerable structural expenditure and the loads which are applied by the slider to the catch pawl must also be taken up by the catch lever and by the pivotal mountings for the pawl and the catch lever. Because said loads are suddeenly applied, they require that the materials, the shapes and the dimensions of the parts which cooperate to catch the slider are properly selected. The parts must be made of high-strength materials, particularly of hardened steel, so that the parts are heavy and can be manufactured and particularly machined only with difficulty. Nevertheless, very strong forces, which may be exerted, e.g., when the firearm falls on the ground, may result in an inadvertent release of the slider so that a round is inadvertently discharged.
EP-A No. 1-0 121 871 and Published German Application No. 23 23 352 disclose trigger mechanisms which comprise spring-loaded catch pawls, which are pivoted directly to the trigger housing and serve to catch the breechblock. Said catch pawls are operable by means of a lever, which cooperates with the trigger. That lever is also spring-loaded and either has a nose which enters a recess of the catch pawl or is connected to the catch pawl by a rotatable pinion, which upon an actuation of the trigger is pivotally moved to move the catch pawl to a releasing position against the force of the catch pawl spring. As the trigger is released, said lever is swung back by spring force so that the catch pawl can jump up to its catching position. Special controlling means including separate control levers, which protrude into the path of the breechblock, are provided and ensure that the release of the catch pawl will be performed exactly when the breechblock has moved to the desired position and that the catching position will properly be assumed. In such an arrangement the loads which are applied to the catch pawl as the breechblock is caught can directly be transmitted by the catch pawl to the trigger housing but the mechanisms described are heavy and expensive and intended for use in automatic cannons and cannot be incorporated in hand-held firearms.
Published German Application No. 32 27 180 discloses self-loading pistols in which the loading mechanism comprises an actuating lever, which engages a two-armed lever that is approximately parallel to the path for the breechblock, one arm of the two-armed lever cooperates with a pivoted breechblock locking member and the other arm of the two-armed lever cooperates with a acatch pawl associated with the striking hammer. In such an arrangement the breechblock locking member is forced upwardly into the path for the breechblock by a nose of the magazine and after the discharge of the last cartridge catches the breechblock in its rear position. In that case the operating lever can be operated so that the two-armed lever will cause the breechblock to be released and the striking hammer to be uncocked. Said self-loading pistols are single-round firearms, in which the trigger is not directly connected to the loading means and in which an actuation of the trigger will cause the striking hammer to be cocked and when a release position has been reached to be released for the discharge of a round independently of the operating lever and the two-armed lever.